Apparatus And Method For Transmission Power Balance Adjustment In A Mobile Cellular System - Patent 8107990

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Apparatus And Method For Transmission Power Balance Adjustment In A Mobile Cellular System - Patent 8107990 Powered By Docstoc
					
				
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Description: 1. Field of Invention The present invention relates generally to a transmission power control system, a control method, a base station and a control station and a storage medium recording a control program. More particularly, the invention relates to a method fordetermining a balance adjustment start timing upon performing balance adjustment of a transmission power for one mobile station from a plurality of base stations at the occurrence of soft hand-over in cellular communication system. 2. Description of Related Art In a code division multiplex cellular system, a plurality of channels use the same frequency, a reception power (desired wave power) of a signal at certain channel becomes an interference wave power to be jamming for other channels. Accordingly, in an uplink transmitted from a mobile station to a base station, when the desired wave power is greater than or equal to a predetermined value, interference wave power is increased to reduce capacity of the channel. In order to preventthis, it becomes necessary to strictly control the transmission power of the mobile station. The transmission power control in the uplink is performed in such a manner that the base station measures the desired wave power to compare with a targetcontrol value for transmitting a up control instruction for reducing a transmission power (hereinafter referred to as "up transmission power") of the uplink for the mobile station when the desired power is larger than the target control value, and fortransmitting the up control instruction for increasing the up transmission power for the mobile station when the desired wave power is smaller than the target control value. Then, the mobile station increases or decreases the up transmission poweraccording to the up control instruction. Transmission of the up control instruction in the transmission power control is performed using a downlink transmitting from the base station to the mobile station. On the other hand, even in the down